Rythm Dreem headband promises you'll sleep better wearing it

Rythm CEO talks about the sleep improving headband
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A good night's sleep is an essential ingredient for a healthy life. It sounds as simple as closing your eyes and drifting off, or counting sheep to lull yourself to sleep, however it's actually far more complicated than that. Most people struggle to get the right amount of Z's or even have a hard time falling asleep in the first place.

There are also plenty of devices that want to help you nod off easier but none that promise medical grade accuracy or have had a team of scientists, engineers, data analysts and even chemists create a sleep wearable that hacks into your brain to help you get the best night of sleep possible.

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That's where Dreem comes in. Developed by Paris-based startup Rythm, the Dreem headband promises to be an "active" wearable that doesn't merely monitor your sleep and report back to you via an app. Rather, it will influence your brain waves to remain in deep sleep longer through a non-invasive sound stimulation.

CEO and co-founder Hugo Mercier sat down and gave us an in-depth look behind the making of the Dreem sleep wearable and its place in the expanding field of neurotechnology.

The science of sleep and Dreem

The Rythm company was created in 2014 through a French engineering school interested in neurology and the human brain. Mercier and several other neuroscientists joined up with research teams in Paris to devise a way to stimulate the brain during sleep in order to increase sleep quality.

There have been countless sleep studies over the years with much progress, but not many consumer products can accurately judge your patterns or give suggestions on how to sleep better.

Mercier says about a third of the general population suffers from a bad night's sleep. "If you ask the other two thirds of the population, 'do you want to sleep more, sleep better and have better performance during the day' they'll likely say yes."

He then adds that the key to sleeping well is in the brain waves, which is how the Dreem headband was born. And to understand how the wearable works, you must understand sleep.

There are several stages of sleep that are repeated in cycles throughout the night. According to Mercier, research has been heavily focused on REM, but from the last few decades, there's been more focus on deep sleep. The Dreem headband was made to understand which stage of sleep you're in, then trigger sounds synchronized with certain patterns that's been read from the brain activity.

"You go faster into deep sleep, which is the first round of stimulation. The second round is during deep sleep to help the brain stay in the stage longer," Mercier tells us. "Basically, we are reading the brain activity, looking for patterns and triggering stimulations at certain points of your night.

A metaphor is your brain is acting like a pendulum during deep sleep. Each time the pendulum is in an upstate, we are triggering a stimulation so it helps the pendulum keep the oscillation and movement.

Deep sleep is also correlated to performances that affect you in the day both cognitively and physically."

There are three main parts in the Dreem headband that help do all of this. Mercier says the electronics are quite complex because it's a wearable computer that needs huge computational power. All the algorithms are running unaided inside the device.

The team also developed its own electrodes. Rythm started testing and prototyping with medical grade electroencephalography (EEG) sensors that require conductive gel - which obviously isn't ideal for a wearable.

Rythm Dreem headband promises you'll sleep better wearing it

"It was a huge change to go from medical grade EEG's to this. They are pieces of metal that are glued to something that is soft, flexible and comfortable. We had to do a lot of researching and chemistry and materials, and physics to develop the sensors."

There are five sensors on the Dreem device. Three are on the forehead, and two flexible ones that go above the ear. The brain's EEG is measured by the sensors and the information is sent to the electronics where the algorithm figures out which stage you are in and when to trigger stimulations.

The stimulations are made through connections as a way of making sound without adding uncomfortable earphones or earplugs to the wearable.

"It's similar to when you put your fingers in your ears and you can still hear your voice because of the micro-vibrations going from your throat to your inner ear. That then becomes an electrical impulse in the brain."

The sound itself is whole other kind of science called "noise color." White noise is probably the one you're most familiar with but Dreem primarily employs pink noise. Noise color is determined by the frequencies present.

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"We are using a pink noise that is like a shot of wind sound that's very short. What is happening is we are sending this impulse and this sound at a particular moment, which is translated by the inner ear into an electrical impulse which is transferred to the brain that is already oscillating."

Because people will react differently to different sounds, the company will fine tune the noise by playing it at different times, playing different types and so forth to see what will work best for various individuals.

Using the Dreem app

Rythm Dreem headband promises you'll sleep better wearing it

It all connects up to an app on your smartphone. Mercier says he didn't want a complicated UI that would bog down the user. "We really wanted to make it short. You won't spend two or three minutes on it." You simply turn on the device, place it on your head, then use the app to ensure everything is in place.

The app itself has several features including a smart alarm clock that will wake you up progressively at the optimal time, sleep data and sleep monitoring that shows advanced accurate data from your night's sleep, and mood/activities where in addition to what the headband is already accumulating, the info you input is used to give more accurate advice for improved sleeping habits.

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For example, you can tag different things like, 'I drank beers, or I played a sport' to show that you're more tired on a certain days where Dreem will in turn tell you to sleep earlier to get more rest.

"The evolution we see is understanding everything about the way you sleep. It's also understanding what you did during the day. Based on that, you can compare what you did and how you slept and you can personalize everything. So we know that next Thursday you need to sleep for six and a half hours, you need to go to bed at this time, you need to wake up at this time.

We want to go in the direction of a kind of artificial intelligence of sleep that can understand all your patterns and your day as well."

Inaccuracies of sleep tracking

Mercier sees a future where wristy wearables will be added to enhance the activity feature found in the app. He says the next version will be the best time to try it since the company will have much more information. The inclusion of another device could provide more information and better personalize the experience.

The main limitation of traditional wearables is they're missing this step: being active.

However, that's not to say current-gen wrist-ware is up to snuff in Mercier's eyes. He says the problem with these trackers is that they're not accurately monitoring your sleeping habits.

"The accelerometers (in activity trackers) are not accurate because what they see is movement during the night. If you move, you're in light sleep. If you don't, you're in deep sleep. That's not accurate at all since the real definition of sleep stages is based on brain activity, through the EEG - basically what's happening inside the brain.

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The second problem with that (wearables) is they're only monitoring. So they're only going to tell you that you didn't sleep well yesterday but it's not going to directly help you improve your sleep. The main limitation of traditional wearables is they're missing this step: being active. The Dreem headband is the first active wearable to increase sleep."

What's next for the Dreem team

Right now, the company is focusing on a limited release of its first non-prototype headband. Dreem can already last 12-14 hours, depending on usage, and has already been shrunk down and redesigned for better comfort and fit since it was first shown off as a prototype at CES earlier this year.

The wearable will go through another round of tweaks through a Dreem First Program where 500 select individuals will get to test out the headband for $350.

But that's not all Rythm wants to do - it has big plans for the future of its technology that include VR.

"Dreem is about sleep, we're going to have a lot of challenges and things to do because sleep has been the only area that hasn't benefitted from technology yet," Mercier tells us.

"All the technologies we have developed for Dreem - wearable computers that can analyze your brain activity in real time, and then trigger stimulations - can be used for other applications.

We have education and personalizing content in how you learn, a brain computer interface like controlling a computer with brain activity without a keyboard, and virtual reality.

By pairing neurotechnology with Oculus Rift for example, we can move in the virtual world, without actually moving. Or change sounds, colors, music, all based on your mood or what you're thinking which would make the experience even more immersive."

Exciting as that sounds, all that's a bit further down the road. Right now, Dreem will be at the forefront of Rythm's agenda, priding themselves on the accuracy of the device.

"There aren't a lot of neurotechnology products looking for accuracy. They're more for entertainment and you don't need to examine brain activity that closely.

In our case we need to. We have a window of five milliseconds on a signal. If you do not have medical grade equipment accuracy, it's not going to work."

We'll be sure to test Dreem ourselves to let you know just how many winks we manage to catch.

How we test


Lily is a writer and editor specializing in tech, video games, marketing, education, travel writing, and creative fiction. 

She has over 10 years of experience covering the technology beat.

Lily has a passion for VR and AR technologies and was associate wearables editor at TechRadar US, before joining Wareable as US editor in 2016.

Lily will graduate in 2023 with an MFA in Creative Writing.

In her spare time, Lily can be found knee-deep in zine collaborations, novel writing, playing Dungeons & Dragons or hiking and foraging for mushrooms.

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